1 /**
2  * Microchip ENCX24J600 ethernet driver
3  *
4  * Copyright (C) 2015 Gridpoint
5  * Author: Jon Ringle <jringle@gridpoint.com>
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License as published by
9  * the Free Software Foundation; either version 2 of the License, or
10  * (at your option) any later version.
11  *
12  */
13 
14 #include <linux/device.h>
15 #include <linux/errno.h>
16 #include <linux/etherdevice.h>
17 #include <linux/ethtool.h>
18 #include <linux/interrupt.h>
19 #include <linux/kernel.h>
20 #include <linux/module.h>
21 #include <linux/netdevice.h>
22 #include <linux/regmap.h>
23 #include <linux/skbuff.h>
24 #include <linux/spi/spi.h>
25 
26 #include "encx24j600_hw.h"
27 
28 #define DRV_NAME	"encx24j600"
29 #define DRV_VERSION	"1.0"
30 
31 #define DEFAULT_MSG_ENABLE (NETIF_MSG_DRV | NETIF_MSG_PROBE | NETIF_MSG_LINK)
32 static int debug = -1;
33 module_param(debug, int, 0);
34 MODULE_PARM_DESC(debug, "Debug level (0=none,...,16=all)");
35 
36 /* SRAM memory layout:
37  *
38  * 0x0000-0x05ff TX buffers  1.5KB  (1*1536) reside in the GP area in SRAM
39  * 0x0600-0x5fff RX buffers 22.5KB (15*1536) reside in the RX area in SRAM
40  */
41 #define ENC_TX_BUF_START 0x0000U
42 #define ENC_RX_BUF_START 0x0600U
43 #define ENC_RX_BUF_END   0x5fffU
44 #define ENC_SRAM_SIZE    0x6000U
45 
46 enum {
47 	RXFILTER_NORMAL,
48 	RXFILTER_MULTI,
49 	RXFILTER_PROMISC
50 };
51 
52 struct encx24j600_priv {
53 	struct net_device        *ndev;
54 	struct mutex              lock; /* device access lock */
55 	struct encx24j600_context ctx;
56 	struct sk_buff           *tx_skb;
57 	struct task_struct       *kworker_task;
58 	struct kthread_worker     kworker;
59 	struct kthread_work       tx_work;
60 	struct kthread_work       setrx_work;
61 	u16                       next_packet;
62 	bool                      hw_enabled;
63 	bool                      full_duplex;
64 	bool                      autoneg;
65 	u16                       speed;
66 	int                       rxfilter;
67 	u32                       msg_enable;
68 };
69 
70 static void dump_packet(const char *msg, int len, const char *data)
71 {
72 	pr_debug(DRV_NAME ": %s - packet len:%d\n", msg, len);
73 	print_hex_dump_bytes("pk data: ", DUMP_PREFIX_OFFSET, data, len);
74 }
75 
76 static void encx24j600_dump_rsv(struct encx24j600_priv *priv, const char *msg,
77 				struct rsv *rsv)
78 {
79 	struct net_device *dev = priv->ndev;
80 
81 	netdev_info(dev, "RX packet Len:%d\n", rsv->len);
82 	netdev_dbg(dev, "%s - NextPk: 0x%04x\n", msg,
83 		   rsv->next_packet);
84 	netdev_dbg(dev, "RxOK: %d, DribbleNibble: %d\n",
85 		   RSV_GETBIT(rsv->rxstat, RSV_RXOK),
86 		   RSV_GETBIT(rsv->rxstat, RSV_DRIBBLENIBBLE));
87 	netdev_dbg(dev, "CRCErr:%d, LenChkErr: %d, LenOutOfRange: %d\n",
88 		   RSV_GETBIT(rsv->rxstat, RSV_CRCERROR),
89 		   RSV_GETBIT(rsv->rxstat, RSV_LENCHECKERR),
90 		   RSV_GETBIT(rsv->rxstat, RSV_LENOUTOFRANGE));
91 	netdev_dbg(dev, "Multicast: %d, Broadcast: %d, LongDropEvent: %d, CarrierEvent: %d\n",
92 		   RSV_GETBIT(rsv->rxstat, RSV_RXMULTICAST),
93 		   RSV_GETBIT(rsv->rxstat, RSV_RXBROADCAST),
94 		   RSV_GETBIT(rsv->rxstat, RSV_RXLONGEVDROPEV),
95 		   RSV_GETBIT(rsv->rxstat, RSV_CARRIEREV));
96 	netdev_dbg(dev, "ControlFrame: %d, PauseFrame: %d, UnknownOp: %d, VLanTagFrame: %d\n",
97 		   RSV_GETBIT(rsv->rxstat, RSV_RXCONTROLFRAME),
98 		   RSV_GETBIT(rsv->rxstat, RSV_RXPAUSEFRAME),
99 		   RSV_GETBIT(rsv->rxstat, RSV_RXUNKNOWNOPCODE),
100 		   RSV_GETBIT(rsv->rxstat, RSV_RXTYPEVLAN));
101 }
102 
103 static u16 encx24j600_read_reg(struct encx24j600_priv *priv, u8 reg)
104 {
105 	struct net_device *dev = priv->ndev;
106 	unsigned int val = 0;
107 	int ret = regmap_read(priv->ctx.regmap, reg, &val);
108 	if (unlikely(ret))
109 		netif_err(priv, drv, dev, "%s: error %d reading reg %02x\n",
110 			  __func__, ret, reg);
111 	return val;
112 }
113 
114 static void encx24j600_write_reg(struct encx24j600_priv *priv, u8 reg, u16 val)
115 {
116 	struct net_device *dev = priv->ndev;
117 	int ret = regmap_write(priv->ctx.regmap, reg, val);
118 	if (unlikely(ret))
119 		netif_err(priv, drv, dev, "%s: error %d writing reg %02x=%04x\n",
120 			  __func__, ret, reg, val);
121 }
122 
123 static void encx24j600_update_reg(struct encx24j600_priv *priv, u8 reg,
124 				  u16 mask, u16 val)
125 {
126 	struct net_device *dev = priv->ndev;
127 	int ret = regmap_update_bits(priv->ctx.regmap, reg, mask, val);
128 	if (unlikely(ret))
129 		netif_err(priv, drv, dev, "%s: error %d updating reg %02x=%04x~%04x\n",
130 			  __func__, ret, reg, val, mask);
131 }
132 
133 static u16 encx24j600_read_phy(struct encx24j600_priv *priv, u8 reg)
134 {
135 	struct net_device *dev = priv->ndev;
136 	unsigned int val = 0;
137 	int ret = regmap_read(priv->ctx.phymap, reg, &val);
138 	if (unlikely(ret))
139 		netif_err(priv, drv, dev, "%s: error %d reading %02x\n",
140 			  __func__, ret, reg);
141 	return val;
142 }
143 
144 static void encx24j600_write_phy(struct encx24j600_priv *priv, u8 reg, u16 val)
145 {
146 	struct net_device *dev = priv->ndev;
147 	int ret = regmap_write(priv->ctx.phymap, reg, val);
148 	if (unlikely(ret))
149 		netif_err(priv, drv, dev, "%s: error %d writing reg %02x=%04x\n",
150 			  __func__, ret, reg, val);
151 }
152 
153 static void encx24j600_clr_bits(struct encx24j600_priv *priv, u8 reg, u16 mask)
154 {
155 	encx24j600_update_reg(priv, reg, mask, 0);
156 }
157 
158 static void encx24j600_set_bits(struct encx24j600_priv *priv, u8 reg, u16 mask)
159 {
160 	encx24j600_update_reg(priv, reg, mask, mask);
161 }
162 
163 static void encx24j600_cmd(struct encx24j600_priv *priv, u8 cmd)
164 {
165 	struct net_device *dev = priv->ndev;
166 	int ret = regmap_write(priv->ctx.regmap, cmd, 0);
167 	if (unlikely(ret))
168 		netif_err(priv, drv, dev, "%s: error %d with cmd %02x\n",
169 			  __func__, ret, cmd);
170 }
171 
172 static int encx24j600_raw_read(struct encx24j600_priv *priv, u8 reg, u8 *data,
173 			       size_t count)
174 {
175 	int ret;
176 	mutex_lock(&priv->ctx.mutex);
177 	ret = regmap_encx24j600_spi_read(&priv->ctx, reg, data, count);
178 	mutex_unlock(&priv->ctx.mutex);
179 
180 	return ret;
181 }
182 
183 static int encx24j600_raw_write(struct encx24j600_priv *priv, u8 reg,
184 				const u8 *data, size_t count)
185 {
186 	int ret;
187 	mutex_lock(&priv->ctx.mutex);
188 	ret = regmap_encx24j600_spi_write(&priv->ctx, reg, data, count);
189 	mutex_unlock(&priv->ctx.mutex);
190 
191 	return ret;
192 }
193 
194 static void encx24j600_update_phcon1(struct encx24j600_priv *priv)
195 {
196 	u16 phcon1 = encx24j600_read_phy(priv, PHCON1);
197 	if (priv->autoneg == AUTONEG_ENABLE) {
198 		phcon1 |= ANEN | RENEG;
199 	} else {
200 		phcon1 &= ~ANEN;
201 		if (priv->speed == SPEED_100)
202 			phcon1 |= SPD100;
203 		else
204 			phcon1 &= ~SPD100;
205 
206 		if (priv->full_duplex)
207 			phcon1 |= PFULDPX;
208 		else
209 			phcon1 &= ~PFULDPX;
210 	}
211 	encx24j600_write_phy(priv, PHCON1, phcon1);
212 }
213 
214 /* Waits for autonegotiation to complete. */
215 static int encx24j600_wait_for_autoneg(struct encx24j600_priv *priv)
216 {
217 	struct net_device *dev = priv->ndev;
218 	unsigned long timeout = jiffies + msecs_to_jiffies(2000);
219 	u16 phstat1;
220 	u16 estat;
221 	int ret = 0;
222 
223 	phstat1 = encx24j600_read_phy(priv, PHSTAT1);
224 	while ((phstat1 & ANDONE) == 0) {
225 		if (time_after(jiffies, timeout)) {
226 			u16 phstat3;
227 
228 			netif_notice(priv, drv, dev, "timeout waiting for autoneg done\n");
229 
230 			priv->autoneg = AUTONEG_DISABLE;
231 			phstat3 = encx24j600_read_phy(priv, PHSTAT3);
232 			priv->speed = (phstat3 & PHY3SPD100)
233 				      ? SPEED_100 : SPEED_10;
234 			priv->full_duplex = (phstat3 & PHY3DPX) ? 1 : 0;
235 			encx24j600_update_phcon1(priv);
236 			netif_notice(priv, drv, dev, "Using parallel detection: %s/%s",
237 				     priv->speed == SPEED_100 ? "100" : "10",
238 				     priv->full_duplex ? "Full" : "Half");
239 
240 			return -ETIMEDOUT;
241 		}
242 		cpu_relax();
243 		phstat1 = encx24j600_read_phy(priv, PHSTAT1);
244 	}
245 
246 	estat = encx24j600_read_reg(priv, ESTAT);
247 	if (estat & PHYDPX) {
248 		encx24j600_set_bits(priv, MACON2, FULDPX);
249 		encx24j600_write_reg(priv, MABBIPG, 0x15);
250 	} else {
251 		encx24j600_clr_bits(priv, MACON2, FULDPX);
252 		encx24j600_write_reg(priv, MABBIPG, 0x12);
253 		/* Max retransmittions attempt  */
254 		encx24j600_write_reg(priv, MACLCON, 0x370f);
255 	}
256 
257 	return ret;
258 }
259 
260 /* Access the PHY to determine link status */
261 static void encx24j600_check_link_status(struct encx24j600_priv *priv)
262 {
263 	struct net_device *dev = priv->ndev;
264 	u16 estat;
265 
266 	estat = encx24j600_read_reg(priv, ESTAT);
267 
268 	if (estat & PHYLNK) {
269 		if (priv->autoneg == AUTONEG_ENABLE)
270 			encx24j600_wait_for_autoneg(priv);
271 
272 		netif_carrier_on(dev);
273 		netif_info(priv, ifup, dev, "link up\n");
274 	} else {
275 		netif_info(priv, ifdown, dev, "link down\n");
276 
277 		/* Re-enable autoneg since we won't know what we might be
278 		 * connected to when the link is brought back up again.
279 		 */
280 		priv->autoneg  = AUTONEG_ENABLE;
281 		priv->full_duplex = true;
282 		priv->speed = SPEED_100;
283 		netif_carrier_off(dev);
284 	}
285 }
286 
287 static void encx24j600_int_link_handler(struct encx24j600_priv *priv)
288 {
289 	struct net_device *dev = priv->ndev;
290 
291 	netif_dbg(priv, intr, dev, "%s", __func__);
292 	encx24j600_check_link_status(priv);
293 	encx24j600_clr_bits(priv, EIR, LINKIF);
294 }
295 
296 static void encx24j600_tx_complete(struct encx24j600_priv *priv, bool err)
297 {
298 	struct net_device *dev = priv->ndev;
299 
300 	if (!priv->tx_skb) {
301 		BUG();
302 		return;
303 	}
304 
305 	mutex_lock(&priv->lock);
306 
307 	if (err)
308 		dev->stats.tx_errors++;
309 	else
310 		dev->stats.tx_packets++;
311 
312 	dev->stats.tx_bytes += priv->tx_skb->len;
313 
314 	encx24j600_clr_bits(priv, EIR, TXIF | TXABTIF);
315 
316 	netif_dbg(priv, tx_done, dev, "TX Done%s\n", err ? ": Err" : "");
317 
318 	dev_kfree_skb(priv->tx_skb);
319 	priv->tx_skb = NULL;
320 
321 	netif_wake_queue(dev);
322 
323 	mutex_unlock(&priv->lock);
324 }
325 
326 static int encx24j600_receive_packet(struct encx24j600_priv *priv,
327 				     struct rsv *rsv)
328 {
329 	struct net_device *dev = priv->ndev;
330 	struct sk_buff *skb = netdev_alloc_skb(dev, rsv->len + NET_IP_ALIGN);
331 	if (!skb) {
332 		pr_err_ratelimited("RX: OOM: packet dropped\n");
333 		dev->stats.rx_dropped++;
334 		return -ENOMEM;
335 	}
336 	skb_reserve(skb, NET_IP_ALIGN);
337 	encx24j600_raw_read(priv, RRXDATA, skb_put(skb, rsv->len), rsv->len);
338 
339 	if (netif_msg_pktdata(priv))
340 		dump_packet("RX", skb->len, skb->data);
341 
342 	skb->dev = dev;
343 	skb->protocol = eth_type_trans(skb, dev);
344 	skb->ip_summed = CHECKSUM_COMPLETE;
345 
346 	/* Maintain stats */
347 	dev->stats.rx_packets++;
348 	dev->stats.rx_bytes += rsv->len;
349 	priv->next_packet = rsv->next_packet;
350 
351 	netif_rx(skb);
352 
353 	return 0;
354 }
355 
356 static void encx24j600_rx_packets(struct encx24j600_priv *priv, u8 packet_count)
357 {
358 	struct net_device *dev = priv->ndev;
359 
360 	while (packet_count--) {
361 		struct rsv rsv;
362 		u16 newrxtail;
363 
364 		encx24j600_write_reg(priv, ERXRDPT, priv->next_packet);
365 		encx24j600_raw_read(priv, RRXDATA, (u8 *)&rsv, sizeof(rsv));
366 
367 		if (netif_msg_rx_status(priv))
368 			encx24j600_dump_rsv(priv, __func__, &rsv);
369 
370 		if (!RSV_GETBIT(rsv.rxstat, RSV_RXOK) ||
371 		    (rsv.len > MAX_FRAMELEN)) {
372 			netif_err(priv, rx_err, dev, "RX Error %04x\n",
373 				  rsv.rxstat);
374 			dev->stats.rx_errors++;
375 
376 			if (RSV_GETBIT(rsv.rxstat, RSV_CRCERROR))
377 				dev->stats.rx_crc_errors++;
378 			if (RSV_GETBIT(rsv.rxstat, RSV_LENCHECKERR))
379 				dev->stats.rx_frame_errors++;
380 			if (rsv.len > MAX_FRAMELEN)
381 				dev->stats.rx_over_errors++;
382 		} else {
383 			encx24j600_receive_packet(priv, &rsv);
384 		}
385 
386 		newrxtail = priv->next_packet - 2;
387 		if (newrxtail == ENC_RX_BUF_START)
388 			newrxtail = SRAM_SIZE - 2;
389 
390 		encx24j600_cmd(priv, SETPKTDEC);
391 		encx24j600_write_reg(priv, ERXTAIL, newrxtail);
392 	}
393 }
394 
395 static irqreturn_t encx24j600_isr(int irq, void *dev_id)
396 {
397 	struct encx24j600_priv *priv = dev_id;
398 	struct net_device *dev = priv->ndev;
399 	int eir;
400 
401 	/* Clear interrupts */
402 	encx24j600_cmd(priv, CLREIE);
403 
404 	eir = encx24j600_read_reg(priv, EIR);
405 
406 	if (eir & LINKIF)
407 		encx24j600_int_link_handler(priv);
408 
409 	if (eir & TXIF)
410 		encx24j600_tx_complete(priv, false);
411 
412 	if (eir & TXABTIF)
413 		encx24j600_tx_complete(priv, true);
414 
415 	if (eir & RXABTIF) {
416 		if (eir & PCFULIF) {
417 			/* Packet counter is full */
418 			netif_err(priv, rx_err, dev, "Packet counter full\n");
419 		}
420 		dev->stats.rx_dropped++;
421 		encx24j600_clr_bits(priv, EIR, RXABTIF);
422 	}
423 
424 	if (eir & PKTIF) {
425 		u8 packet_count;
426 
427 		mutex_lock(&priv->lock);
428 
429 		packet_count = encx24j600_read_reg(priv, ESTAT) & 0xff;
430 		while (packet_count) {
431 			encx24j600_rx_packets(priv, packet_count);
432 			packet_count = encx24j600_read_reg(priv, ESTAT) & 0xff;
433 		}
434 
435 		mutex_unlock(&priv->lock);
436 	}
437 
438 	/* Enable interrupts */
439 	encx24j600_cmd(priv, SETEIE);
440 
441 	return IRQ_HANDLED;
442 }
443 
444 static int encx24j600_soft_reset(struct encx24j600_priv *priv)
445 {
446 	int ret = 0;
447 	int timeout;
448 	u16 eudast;
449 
450 	/* Write and verify a test value to EUDAST */
451 	regcache_cache_bypass(priv->ctx.regmap, true);
452 	timeout = 10;
453 	do {
454 		encx24j600_write_reg(priv, EUDAST, EUDAST_TEST_VAL);
455 		eudast = encx24j600_read_reg(priv, EUDAST);
456 		usleep_range(25, 100);
457 	} while ((eudast != EUDAST_TEST_VAL) && --timeout);
458 	regcache_cache_bypass(priv->ctx.regmap, false);
459 
460 	if (timeout == 0) {
461 		ret = -ETIMEDOUT;
462 		goto err_out;
463 	}
464 
465 	/* Wait for CLKRDY to become set */
466 	timeout = 10;
467 	while (!(encx24j600_read_reg(priv, ESTAT) & CLKRDY) && --timeout)
468 		usleep_range(25, 100);
469 
470 	if (timeout == 0) {
471 		ret = -ETIMEDOUT;
472 		goto err_out;
473 	}
474 
475 	/* Issue a System Reset command */
476 	encx24j600_cmd(priv, SETETHRST);
477 	usleep_range(25, 100);
478 
479 	/* Confirm that EUDAST has 0000h after system reset */
480 	if (encx24j600_read_reg(priv, EUDAST) != 0) {
481 		ret = -EINVAL;
482 		goto err_out;
483 	}
484 
485 	/* Wait for PHY register and status bits to become available */
486 	usleep_range(256, 1000);
487 
488 err_out:
489 	return ret;
490 }
491 
492 static int encx24j600_hw_reset(struct encx24j600_priv *priv)
493 {
494 	int ret;
495 
496 	mutex_lock(&priv->lock);
497 	ret = encx24j600_soft_reset(priv);
498 	mutex_unlock(&priv->lock);
499 
500 	return ret;
501 }
502 
503 static void encx24j600_reset_hw_tx(struct encx24j600_priv *priv)
504 {
505 	encx24j600_set_bits(priv, ECON2, TXRST);
506 	encx24j600_clr_bits(priv, ECON2, TXRST);
507 }
508 
509 static void encx24j600_hw_init_tx(struct encx24j600_priv *priv)
510 {
511 	/* Reset TX */
512 	encx24j600_reset_hw_tx(priv);
513 
514 	/* Clear the TXIF flag if were previously set */
515 	encx24j600_clr_bits(priv, EIR, TXIF | TXABTIF);
516 
517 	/* Write the Tx Buffer pointer */
518 	encx24j600_write_reg(priv, EGPWRPT, ENC_TX_BUF_START);
519 }
520 
521 static void encx24j600_hw_init_rx(struct encx24j600_priv *priv)
522 {
523 	encx24j600_cmd(priv, DISABLERX);
524 
525 	/* Set up RX packet start address in the SRAM */
526 	encx24j600_write_reg(priv, ERXST, ENC_RX_BUF_START);
527 
528 	/* Preload the RX Data pointer to the beginning of the RX area */
529 	encx24j600_write_reg(priv, ERXRDPT, ENC_RX_BUF_START);
530 
531 	priv->next_packet = ENC_RX_BUF_START;
532 
533 	/* Set up RX end address in the SRAM */
534 	encx24j600_write_reg(priv, ERXTAIL, ENC_SRAM_SIZE - 2);
535 
536 	/* Reset the  user data pointers    */
537 	encx24j600_write_reg(priv, EUDAST, ENC_SRAM_SIZE);
538 	encx24j600_write_reg(priv, EUDAND, ENC_SRAM_SIZE + 1);
539 
540 	/* Set Max Frame length */
541 	encx24j600_write_reg(priv, MAMXFL, MAX_FRAMELEN);
542 }
543 
544 static void encx24j600_dump_config(struct encx24j600_priv *priv,
545 				   const char *msg)
546 {
547 	pr_info(DRV_NAME ": %s\n", msg);
548 
549 	/* CHIP configuration */
550 	pr_info(DRV_NAME " ECON1:   %04X\n", encx24j600_read_reg(priv, ECON1));
551 	pr_info(DRV_NAME " ECON2:   %04X\n", encx24j600_read_reg(priv, ECON2));
552 	pr_info(DRV_NAME " ERXFCON: %04X\n", encx24j600_read_reg(priv,
553 								 ERXFCON));
554 	pr_info(DRV_NAME " ESTAT:   %04X\n", encx24j600_read_reg(priv, ESTAT));
555 	pr_info(DRV_NAME " EIR:     %04X\n", encx24j600_read_reg(priv, EIR));
556 	pr_info(DRV_NAME " EIDLED:  %04X\n", encx24j600_read_reg(priv, EIDLED));
557 
558 	/* MAC layer configuration */
559 	pr_info(DRV_NAME " MACON1:  %04X\n", encx24j600_read_reg(priv, MACON1));
560 	pr_info(DRV_NAME " MACON2:  %04X\n", encx24j600_read_reg(priv, MACON2));
561 	pr_info(DRV_NAME " MAIPG:   %04X\n", encx24j600_read_reg(priv, MAIPG));
562 	pr_info(DRV_NAME " MACLCON: %04X\n", encx24j600_read_reg(priv,
563 								 MACLCON));
564 	pr_info(DRV_NAME " MABBIPG: %04X\n", encx24j600_read_reg(priv,
565 								 MABBIPG));
566 
567 	/* PHY configuation */
568 	pr_info(DRV_NAME " PHCON1:  %04X\n", encx24j600_read_phy(priv, PHCON1));
569 	pr_info(DRV_NAME " PHCON2:  %04X\n", encx24j600_read_phy(priv, PHCON2));
570 	pr_info(DRV_NAME " PHANA:   %04X\n", encx24j600_read_phy(priv, PHANA));
571 	pr_info(DRV_NAME " PHANLPA: %04X\n", encx24j600_read_phy(priv,
572 								 PHANLPA));
573 	pr_info(DRV_NAME " PHANE:   %04X\n", encx24j600_read_phy(priv, PHANE));
574 	pr_info(DRV_NAME " PHSTAT1: %04X\n", encx24j600_read_phy(priv,
575 								 PHSTAT1));
576 	pr_info(DRV_NAME " PHSTAT2: %04X\n", encx24j600_read_phy(priv,
577 								 PHSTAT2));
578 	pr_info(DRV_NAME " PHSTAT3: %04X\n", encx24j600_read_phy(priv,
579 								 PHSTAT3));
580 }
581 
582 static void encx24j600_set_rxfilter_mode(struct encx24j600_priv *priv)
583 {
584 	switch (priv->rxfilter) {
585 	case RXFILTER_PROMISC:
586 		encx24j600_set_bits(priv, MACON1, PASSALL);
587 		encx24j600_write_reg(priv, ERXFCON, UCEN | MCEN | NOTMEEN);
588 		break;
589 	case RXFILTER_MULTI:
590 		encx24j600_clr_bits(priv, MACON1, PASSALL);
591 		encx24j600_write_reg(priv, ERXFCON, UCEN | CRCEN | BCEN | MCEN);
592 		break;
593 	case RXFILTER_NORMAL:
594 	default:
595 		encx24j600_clr_bits(priv, MACON1, PASSALL);
596 		encx24j600_write_reg(priv, ERXFCON, UCEN | CRCEN | BCEN);
597 		break;
598 	}
599 }
600 
601 static int encx24j600_hw_init(struct encx24j600_priv *priv)
602 {
603 	struct net_device *dev = priv->ndev;
604 	int ret = 0;
605 	u16 eidled;
606 	u16 macon2;
607 
608 	priv->hw_enabled = false;
609 
610 	eidled = encx24j600_read_reg(priv, EIDLED);
611 	if (((eidled & DEVID_MASK) >> DEVID_SHIFT) != ENCX24J600_DEV_ID) {
612 		ret = -EINVAL;
613 		goto err_out;
614 	}
615 
616 	netif_info(priv, drv, dev, "Silicon rev ID: 0x%02x\n",
617 		   (eidled & REVID_MASK) >> REVID_SHIFT);
618 
619 	/* PHY Leds: link status,
620 	 * LEDA: Link State + collision events
621 	 * LEDB: Link State + transmit/receive events
622 	 */
623 	encx24j600_update_reg(priv, EIDLED, 0xff00, 0xcb00);
624 
625 	/* Loopback disabled */
626 	encx24j600_write_reg(priv, MACON1, 0x9);
627 
628 	/* interpacket gap value */
629 	encx24j600_write_reg(priv, MAIPG, 0x0c12);
630 
631 	/* Write the auto negotiation pattern */
632 	encx24j600_write_phy(priv, PHANA, PHANA_DEFAULT);
633 
634 	encx24j600_update_phcon1(priv);
635 	encx24j600_check_link_status(priv);
636 
637 	macon2 = MACON2_RSV1 | TXCRCEN | PADCFG0 | PADCFG2 | MACON2_DEFER;
638 	if ((priv->autoneg == AUTONEG_DISABLE) && priv->full_duplex)
639 		macon2 |= FULDPX;
640 
641 	encx24j600_set_bits(priv, MACON2, macon2);
642 
643 	priv->rxfilter = RXFILTER_NORMAL;
644 	encx24j600_set_rxfilter_mode(priv);
645 
646 	/* Program the Maximum frame length */
647 	encx24j600_write_reg(priv, MAMXFL, MAX_FRAMELEN);
648 
649 	/* Init Tx pointers */
650 	encx24j600_hw_init_tx(priv);
651 
652 	/* Init Rx pointers */
653 	encx24j600_hw_init_rx(priv);
654 
655 	if (netif_msg_hw(priv))
656 		encx24j600_dump_config(priv, "Hw is initialized");
657 
658 err_out:
659 	return ret;
660 }
661 
662 static void encx24j600_hw_enable(struct encx24j600_priv *priv)
663 {
664 	/* Clear the interrupt flags in case was set */
665 	encx24j600_clr_bits(priv, EIR, (PCFULIF | RXABTIF | TXABTIF | TXIF |
666 					PKTIF | LINKIF));
667 
668 	/* Enable the interrupts */
669 	encx24j600_write_reg(priv, EIE, (PCFULIE | RXABTIE | TXABTIE | TXIE |
670 					 PKTIE | LINKIE | INTIE));
671 
672 	/* Enable RX */
673 	encx24j600_cmd(priv, ENABLERX);
674 
675 	priv->hw_enabled = true;
676 }
677 
678 static void encx24j600_hw_disable(struct encx24j600_priv *priv)
679 {
680 	/* Disable all interrupts */
681 	encx24j600_write_reg(priv, EIE, 0);
682 
683 	/* Disable RX */
684 	encx24j600_cmd(priv, DISABLERX);
685 
686 	priv->hw_enabled = false;
687 }
688 
689 static int encx24j600_setlink(struct net_device *dev, u8 autoneg, u16 speed,
690 			      u8 duplex)
691 {
692 	struct encx24j600_priv *priv = netdev_priv(dev);
693 	int ret = 0;
694 
695 	if (!priv->hw_enabled) {
696 		/* link is in low power mode now; duplex setting
697 		 * will take effect on next encx24j600_hw_init()
698 		 */
699 		if (speed == SPEED_10 || speed == SPEED_100) {
700 			priv->autoneg = (autoneg == AUTONEG_ENABLE);
701 			priv->full_duplex = (duplex == DUPLEX_FULL);
702 			priv->speed = (speed == SPEED_100);
703 		} else {
704 			netif_warn(priv, link, dev, "unsupported link speed setting\n");
705 			/*speeds other than SPEED_10 and SPEED_100 */
706 			/*are not supported by chip */
707 			ret = -EOPNOTSUPP;
708 		}
709 	} else {
710 		netif_warn(priv, link, dev, "Warning: hw must be disabled to set link mode\n");
711 		ret = -EBUSY;
712 	}
713 	return ret;
714 }
715 
716 static void encx24j600_hw_get_macaddr(struct encx24j600_priv *priv,
717 				      unsigned char *ethaddr)
718 {
719 	unsigned short val;
720 
721 	val = encx24j600_read_reg(priv, MAADR1);
722 
723 	ethaddr[0] = val & 0x00ff;
724 	ethaddr[1] = (val & 0xff00) >> 8;
725 
726 	val = encx24j600_read_reg(priv, MAADR2);
727 
728 	ethaddr[2] = val & 0x00ffU;
729 	ethaddr[3] = (val & 0xff00U) >> 8;
730 
731 	val = encx24j600_read_reg(priv, MAADR3);
732 
733 	ethaddr[4] = val & 0x00ffU;
734 	ethaddr[5] = (val & 0xff00U) >> 8;
735 }
736 
737 /* Program the hardware MAC address from dev->dev_addr.*/
738 static int encx24j600_set_hw_macaddr(struct net_device *dev)
739 {
740 	struct encx24j600_priv *priv = netdev_priv(dev);
741 
742 	if (priv->hw_enabled) {
743 		netif_info(priv, drv, dev, "Hardware must be disabled to set Mac address\n");
744 		return -EBUSY;
745 	}
746 
747 	mutex_lock(&priv->lock);
748 
749 	netif_info(priv, drv, dev, "%s: Setting MAC address to %pM\n",
750 		   dev->name, dev->dev_addr);
751 
752 	encx24j600_write_reg(priv, MAADR3, (dev->dev_addr[4] |
753 			     dev->dev_addr[5] << 8));
754 	encx24j600_write_reg(priv, MAADR2, (dev->dev_addr[2] |
755 			     dev->dev_addr[3] << 8));
756 	encx24j600_write_reg(priv, MAADR1, (dev->dev_addr[0] |
757 			     dev->dev_addr[1] << 8));
758 
759 	mutex_unlock(&priv->lock);
760 
761 	return 0;
762 }
763 
764 /* Store the new hardware address in dev->dev_addr, and update the MAC.*/
765 static int encx24j600_set_mac_address(struct net_device *dev, void *addr)
766 {
767 	struct sockaddr *address = addr;
768 
769 	if (netif_running(dev))
770 		return -EBUSY;
771 	if (!is_valid_ether_addr(address->sa_data))
772 		return -EADDRNOTAVAIL;
773 
774 	memcpy(dev->dev_addr, address->sa_data, dev->addr_len);
775 	return encx24j600_set_hw_macaddr(dev);
776 }
777 
778 static int encx24j600_open(struct net_device *dev)
779 {
780 	struct encx24j600_priv *priv = netdev_priv(dev);
781 
782 	int ret = request_threaded_irq(priv->ctx.spi->irq, NULL, encx24j600_isr,
783 				       IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
784 				       DRV_NAME, priv);
785 	if (unlikely(ret < 0)) {
786 		netdev_err(dev, "request irq %d failed (ret = %d)\n",
787 			   priv->ctx.spi->irq, ret);
788 		return ret;
789 	}
790 
791 	encx24j600_hw_disable(priv);
792 	encx24j600_hw_init(priv);
793 	encx24j600_hw_enable(priv);
794 	netif_start_queue(dev);
795 
796 	return 0;
797 }
798 
799 static int encx24j600_stop(struct net_device *dev)
800 {
801 	struct encx24j600_priv *priv = netdev_priv(dev);
802 
803 	netif_stop_queue(dev);
804 	free_irq(priv->ctx.spi->irq, priv);
805 	return 0;
806 }
807 
808 static void encx24j600_setrx_proc(struct kthread_work *ws)
809 {
810 	struct encx24j600_priv *priv =
811 			container_of(ws, struct encx24j600_priv, setrx_work);
812 
813 	mutex_lock(&priv->lock);
814 	encx24j600_set_rxfilter_mode(priv);
815 	mutex_unlock(&priv->lock);
816 }
817 
818 static void encx24j600_set_multicast_list(struct net_device *dev)
819 {
820 	struct encx24j600_priv *priv = netdev_priv(dev);
821 	int oldfilter = priv->rxfilter;
822 
823 	if (dev->flags & IFF_PROMISC) {
824 		netif_dbg(priv, link, dev, "promiscuous mode\n");
825 		priv->rxfilter = RXFILTER_PROMISC;
826 	} else if ((dev->flags & IFF_ALLMULTI) || !netdev_mc_empty(dev)) {
827 		netif_dbg(priv, link, dev, "%smulticast mode\n",
828 			  (dev->flags & IFF_ALLMULTI) ? "all-" : "");
829 		priv->rxfilter = RXFILTER_MULTI;
830 	} else {
831 		netif_dbg(priv, link, dev, "normal mode\n");
832 		priv->rxfilter = RXFILTER_NORMAL;
833 	}
834 
835 	if (oldfilter != priv->rxfilter)
836 		queue_kthread_work(&priv->kworker, &priv->setrx_work);
837 }
838 
839 static void encx24j600_hw_tx(struct encx24j600_priv *priv)
840 {
841 	struct net_device *dev = priv->ndev;
842 	netif_info(priv, tx_queued, dev, "TX Packet Len:%d\n",
843 		   priv->tx_skb->len);
844 
845 	if (netif_msg_pktdata(priv))
846 		dump_packet("TX", priv->tx_skb->len, priv->tx_skb->data);
847 
848 	if (encx24j600_read_reg(priv, EIR) & TXABTIF)
849 		/* Last transmition aborted due to error. Reset TX interface */
850 		encx24j600_reset_hw_tx(priv);
851 
852 	/* Clear the TXIF flag if were previously set */
853 	encx24j600_clr_bits(priv, EIR, TXIF);
854 
855 	/* Set the data pointer to the TX buffer address in the SRAM */
856 	encx24j600_write_reg(priv, EGPWRPT, ENC_TX_BUF_START);
857 
858 	/* Copy the packet into the SRAM */
859 	encx24j600_raw_write(priv, WGPDATA, (u8 *)priv->tx_skb->data,
860 			     priv->tx_skb->len);
861 
862 	/* Program the Tx buffer start pointer */
863 	encx24j600_write_reg(priv, ETXST, ENC_TX_BUF_START);
864 
865 	/* Program the packet length */
866 	encx24j600_write_reg(priv, ETXLEN, priv->tx_skb->len);
867 
868 	/* Start the transmission */
869 	encx24j600_cmd(priv, SETTXRTS);
870 }
871 
872 static void encx24j600_tx_proc(struct kthread_work *ws)
873 {
874 	struct encx24j600_priv *priv =
875 			container_of(ws, struct encx24j600_priv, tx_work);
876 
877 	mutex_lock(&priv->lock);
878 	encx24j600_hw_tx(priv);
879 	mutex_unlock(&priv->lock);
880 }
881 
882 static netdev_tx_t encx24j600_tx(struct sk_buff *skb, struct net_device *dev)
883 {
884 	struct encx24j600_priv *priv = netdev_priv(dev);
885 
886 	netif_stop_queue(dev);
887 
888 	/* save the timestamp */
889 	dev->trans_start = jiffies;
890 
891 	/* Remember the skb for deferred processing */
892 	priv->tx_skb = skb;
893 
894 	queue_kthread_work(&priv->kworker, &priv->tx_work);
895 
896 	return NETDEV_TX_OK;
897 }
898 
899 /* Deal with a transmit timeout */
900 static void encx24j600_tx_timeout(struct net_device *dev)
901 {
902 	struct encx24j600_priv *priv = netdev_priv(dev);
903 
904 	netif_err(priv, tx_err, dev, "TX timeout at %ld, latency %ld\n",
905 		  jiffies, jiffies - dev->trans_start);
906 
907 	dev->stats.tx_errors++;
908 	netif_wake_queue(dev);
909 	return;
910 }
911 
912 static int encx24j600_get_regs_len(struct net_device *dev)
913 {
914 	return SFR_REG_COUNT;
915 }
916 
917 static void encx24j600_get_regs(struct net_device *dev,
918 				struct ethtool_regs *regs, void *p)
919 {
920 	struct encx24j600_priv *priv = netdev_priv(dev);
921 	u16 *buff = p;
922 	u8 reg;
923 
924 	regs->version = 1;
925 	mutex_lock(&priv->lock);
926 	for (reg = 0; reg < SFR_REG_COUNT; reg += 2) {
927 		unsigned int val = 0;
928 		/* ignore errors for unreadable registers */
929 		regmap_read(priv->ctx.regmap, reg, &val);
930 		buff[reg] = val & 0xffff;
931 	}
932 	mutex_unlock(&priv->lock);
933 }
934 
935 static void encx24j600_get_drvinfo(struct net_device *dev,
936 				   struct ethtool_drvinfo *info)
937 {
938 	strlcpy(info->driver, DRV_NAME, sizeof(info->driver));
939 	strlcpy(info->version, DRV_VERSION, sizeof(info->version));
940 	strlcpy(info->bus_info, dev_name(dev->dev.parent),
941 		sizeof(info->bus_info));
942 }
943 
944 static int encx24j600_get_settings(struct net_device *dev,
945 				   struct ethtool_cmd *cmd)
946 {
947 	struct encx24j600_priv *priv = netdev_priv(dev);
948 
949 	cmd->transceiver = XCVR_INTERNAL;
950 	cmd->supported = SUPPORTED_10baseT_Half | SUPPORTED_10baseT_Full |
951 			 SUPPORTED_100baseT_Half | SUPPORTED_100baseT_Full |
952 			 SUPPORTED_Autoneg | SUPPORTED_TP;
953 
954 	ethtool_cmd_speed_set(cmd, priv->speed);
955 	cmd->duplex = priv->full_duplex ? DUPLEX_FULL : DUPLEX_HALF;
956 	cmd->port = PORT_TP;
957 	cmd->autoneg = priv->autoneg ? AUTONEG_ENABLE : AUTONEG_DISABLE;
958 
959 	return 0;
960 }
961 
962 static int encx24j600_set_settings(struct net_device *dev,
963 				   struct ethtool_cmd *cmd)
964 {
965 	return encx24j600_setlink(dev, cmd->autoneg,
966 				  ethtool_cmd_speed(cmd), cmd->duplex);
967 }
968 
969 static u32 encx24j600_get_msglevel(struct net_device *dev)
970 {
971 	struct encx24j600_priv *priv = netdev_priv(dev);
972 	return priv->msg_enable;
973 }
974 
975 static void encx24j600_set_msglevel(struct net_device *dev, u32 val)
976 {
977 	struct encx24j600_priv *priv = netdev_priv(dev);
978 	priv->msg_enable = val;
979 }
980 
981 static const struct ethtool_ops encx24j600_ethtool_ops = {
982 	.get_settings = encx24j600_get_settings,
983 	.set_settings = encx24j600_set_settings,
984 	.get_drvinfo = encx24j600_get_drvinfo,
985 	.get_msglevel = encx24j600_get_msglevel,
986 	.set_msglevel = encx24j600_set_msglevel,
987 	.get_regs_len = encx24j600_get_regs_len,
988 	.get_regs = encx24j600_get_regs,
989 };
990 
991 static const struct net_device_ops encx24j600_netdev_ops = {
992 	.ndo_open = encx24j600_open,
993 	.ndo_stop = encx24j600_stop,
994 	.ndo_start_xmit = encx24j600_tx,
995 	.ndo_set_rx_mode = encx24j600_set_multicast_list,
996 	.ndo_set_mac_address = encx24j600_set_mac_address,
997 	.ndo_tx_timeout = encx24j600_tx_timeout,
998 	.ndo_validate_addr = eth_validate_addr,
999 };
1000 
1001 static int encx24j600_spi_probe(struct spi_device *spi)
1002 {
1003 	int ret;
1004 
1005 	struct net_device *ndev;
1006 	struct encx24j600_priv *priv;
1007 
1008 	ndev = alloc_etherdev(sizeof(struct encx24j600_priv));
1009 
1010 	if (!ndev) {
1011 		ret = -ENOMEM;
1012 		goto error_out;
1013 	}
1014 
1015 	priv = netdev_priv(ndev);
1016 	spi_set_drvdata(spi, priv);
1017 	dev_set_drvdata(&spi->dev, priv);
1018 	SET_NETDEV_DEV(ndev, &spi->dev);
1019 
1020 	priv->msg_enable = netif_msg_init(debug, DEFAULT_MSG_ENABLE);
1021 	priv->ndev = ndev;
1022 
1023 	/* Default configuration PHY configuration */
1024 	priv->full_duplex = true;
1025 	priv->autoneg = AUTONEG_ENABLE;
1026 	priv->speed = SPEED_100;
1027 
1028 	priv->ctx.spi = spi;
1029 	devm_regmap_init_encx24j600(&spi->dev, &priv->ctx);
1030 	ndev->irq = spi->irq;
1031 	ndev->netdev_ops = &encx24j600_netdev_ops;
1032 
1033 	mutex_init(&priv->lock);
1034 
1035 	/* Reset device and check if it is connected */
1036 	if (encx24j600_hw_reset(priv)) {
1037 		netif_err(priv, probe, ndev,
1038 			  DRV_NAME ": Chip is not detected\n");
1039 		ret = -EIO;
1040 		goto out_free;
1041 	}
1042 
1043 	/* Initialize the device HW to the consistent state */
1044 	if (encx24j600_hw_init(priv)) {
1045 		netif_err(priv, probe, ndev,
1046 			  DRV_NAME ": HW initialization error\n");
1047 		ret = -EIO;
1048 		goto out_free;
1049 	}
1050 
1051 	init_kthread_worker(&priv->kworker);
1052 	init_kthread_work(&priv->tx_work, encx24j600_tx_proc);
1053 	init_kthread_work(&priv->setrx_work, encx24j600_setrx_proc);
1054 
1055 	priv->kworker_task = kthread_run(kthread_worker_fn, &priv->kworker,
1056 					 "encx24j600");
1057 
1058 	if (IS_ERR(priv->kworker_task)) {
1059 		ret = PTR_ERR(priv->kworker_task);
1060 		goto out_free;
1061 	}
1062 
1063 	/* Get the MAC address from the chip */
1064 	encx24j600_hw_get_macaddr(priv, ndev->dev_addr);
1065 
1066 	ndev->ethtool_ops = &encx24j600_ethtool_ops;
1067 
1068 	ret = register_netdev(ndev);
1069 	if (unlikely(ret)) {
1070 		netif_err(priv, probe, ndev, "Error %d initializing card encx24j600 card\n",
1071 			  ret);
1072 		goto out_free;
1073 	}
1074 
1075 	netif_info(priv, drv, priv->ndev, "MAC address %pM\n", ndev->dev_addr);
1076 
1077 	return ret;
1078 
1079 out_free:
1080 	free_netdev(ndev);
1081 
1082 error_out:
1083 	return ret;
1084 }
1085 
1086 static int encx24j600_spi_remove(struct spi_device *spi)
1087 {
1088 	struct encx24j600_priv *priv = dev_get_drvdata(&spi->dev);
1089 
1090 	unregister_netdev(priv->ndev);
1091 
1092 	free_netdev(priv->ndev);
1093 
1094 	return 0;
1095 }
1096 
1097 static const struct spi_device_id encx24j600_spi_id_table[] = {
1098 	{ .name = "encx24j600" },
1099 	{ /* sentinel */ }
1100 };
1101 MODULE_DEVICE_TABLE(spi, encx24j600_spi_id_table);
1102 
1103 static struct spi_driver encx24j600_spi_net_driver = {
1104 	.driver = {
1105 		.name	= DRV_NAME,
1106 		.owner	= THIS_MODULE,
1107 		.bus	= &spi_bus_type,
1108 	},
1109 	.probe		= encx24j600_spi_probe,
1110 	.remove		= encx24j600_spi_remove,
1111 	.id_table	= encx24j600_spi_id_table,
1112 };
1113 
1114 static int __init encx24j600_init(void)
1115 {
1116 	return spi_register_driver(&encx24j600_spi_net_driver);
1117 }
1118 module_init(encx24j600_init);
1119 
1120 static void encx24j600_exit(void)
1121 {
1122 	spi_unregister_driver(&encx24j600_spi_net_driver);
1123 }
1124 module_exit(encx24j600_exit);
1125 
1126 MODULE_DESCRIPTION(DRV_NAME " ethernet driver");
1127 MODULE_AUTHOR("Jon Ringle <jringle@gridpoint.com>");
1128 MODULE_LICENSE("GPL");
1129 MODULE_ALIAS("spi:" DRV_NAME);
1130